Code 75, 76 Or 77, EGR Solenoid Error: Notes

PCM performs an EGR diagnostic check to monitor flow of exhaust gases through 3 EGR solenoids. When vehicle is under deceleration, EGR valves are normally closed. PCM then opens each valve in succession (while keeping previous valves open) and manifold vacuum is monitored for a calculated MAP increase associated with each valve's application. Should expected response of manifold vacuum not be seen by PCM, a Code 75 (solenoid No.1), 76 (solenoid No. 2) or 77 (solenoid No. 3) will set.

1. This test determines if there is power to EGR valve.
2. This test will determine if there is an open circuit in EGR wiring or if the EGR valve is at fault.
3. This test will determine if there is a short to ground in solenoid drive circuits or if PCM is at fault.